Improvement in metallic-alloy paints



UNITED STATES PATENT OFFICE.

CHAS. VVETTERSTEDT, OI MARSEILLES, FRANCE, ASSIGNOR TO CHAS.

' KEENAN.

iMPROVEMENT IN METALLIC-ALLOY PAINTS.

Specification forming part of Letters Patent No. 8,275, dated August 5, 1861.

To all whom it may concern:

Be it known that I, CHARLES DEWETTER- STEDT, of the city of Marseilles, in the Republic of France, have invented a new and useful improvement in covering ships bottoms and other surfaces to prevent their destruction; and I do hereby declare that the following is a full, clear, and exact description thereof.

The basis of my invention consists in the combination or mixture of regulus of antimony in various proportions, purified from all ferruginous particles, with copper, tin, zinc, or lead. These mixtures reduced to impalpable powders are combined with suitable articles to form paint and spread on the surfaces to be pre-- served.

First. When copper isthe metal to be combined with antimony I find that one part of copper and from one-third to one-half part, or a little more, of the purified antimony are suitable proportions of the respective in gredi-- clean mixture, it is ready for use.

Third. In order to combine the copper with the antimony, I melt in a suitable iron vessel coated externally with a proper coating of fireclay about thirty-five pounds of antimony, previously broken up to nut size, and, having melted it, add quickly sixty-five pounds of old sheathingcopper folded and hammered together in close folds. When fully melted the alloy is taken out with an iron or other suitable ladle and poured in a small stream from a vheight of two or three feet into a vessel containin g water, and furnished with any well-known form of agitator for keeping the liquid in motion. The pouring from a height combined with a continual agitation of the water serve to make the granulation of the alloy the more complete. The crucible, when empty, may be immediately refilled with a fresh charge to be a half to two parts of antimony to one part of tin. For zinc l find one part of this metal to one and a half part of antimony to be suitable proportions; but with lead ten of antimony to one of lead is the relation of the quantities. These may require to be varied according to the purity of the respective metals. Even regul'ns of antimony alone may be employed when reduced to fine powder and mixed withlinseedoil, a little spirits of turpentine, and oxide of .zinc.

Fifth. In forming alloysbetween theregulus of antimony and lead, zinc, or tin the fire around the crucible must be much less intense than for the alloy of antimony and copper otherwise the zinc wouldbe liable to loss by evaporation, and the other metals would be made impure by their own oxidation, and the subsequent pulverization would be rendered more difficult and the article produced inferior, while antimony would be lost by evaporation.'

Sixth. The different alloys may be pulverized on a large flat iron plate with a cast-iron muller, similar in its action to the apparatus used by painters for grinding their colors, or in any of the well-known mills, stamps, or mortars adapted to pulverize hard substances, though steel or cast-iron mills are preferred, as least likely to impartimpurities to the alloy. A mull- I er of granite maybe used to finish the grinding. While grinding the alloy is kept moistened with naphtha, ether, or other similar liquid, which prevents the oxidation of the alloy.

Seventh. The different antimonial alloys are formed into paints by mixing them with divers liquids, the proportions of which vary, as well as those of the alloys, according to the metal or other surface which I wish to protect. Two

parts of purified vegetable tar, or the same- 2 see/5 nish of yellow amber. In using the alloy of antimony and copper forthe protection of iron, I form the mixture of six pounds of the pow- .dered alloy with four quarts of a liquid composed of tar and naphtha in equal quantities, and finally add one pint of naphtha. To prepare the iron for receiving this coatI first spread over it a coat of the linseed-oil boiled with litharge; and, secondly, apply two coats of my alloy of antimony and lead, prepared as herein directed, and mixed with the boiled linseed-oil and litharge in the proportion of two pounds of the alloy to one pint of the oil, add ing spirits of turpentine as required to make the paint flow easily.

Eighth. Surfaces ofiron'which are to beplaced under water will, in addition to the above coats of paint, receive another composed of two pounds of the alloy of antimony and copper with four pounds of oxide of copper mixed with five pints of the mixture of tar and naphtha and then three pints of pure naphtha. This last coat is a more completeprotection against the adhesion of barnacles and weeds than the other varieties of paint hereinbefore described.

Ninth. In applying these metallic paints care must be taken to prevent the brush from getting clogged. This is doneby drawing it over the prongs of a Y-shaped metallic fork or prong, and the settling down of the heavy alloy will be obviated by moving the brush around the bottom and sides of the paint-pot when dipping it to take up the paint.

I may here observe that the advantages of employing antimony as a general constituent of metallic paint are threefold: first, it possesses great hardness and power to resist mechanical abrasion from the friction of the water, and this property it imparts to its alloys, as proved by the case of type-metal 5 secondly, both the regulus and its alloys are more brittle than other simple metals or their components, and this property is essential to every metal intended to be ground up and used as paint. Without this property the reduction of any of the metals into a state fit for paint would be attended with great difficulties; thirdly, the covering of copper, yellow metal, or iron ships bottoms with antimony protects them in consequence of the protective effect of its galvanic action; but it keeps them clean at the same time by not running its reaction to protective influence of the antimony; butit is allowed to dissolve just sufficiently to produce a poisoning of animals, &c., adhering to the surface.

Tenth. Iron exposed only to the action of air is protected by the paint formed with the alloy of antimonyand lead or zinc, that formed with the lead being preferred. I apply the use of antimonial alloys to the protection of compound as well as simple'metals, and especially to the protection of sheathing and tubes made of copper, tin, or lead, in which antimony is combined in small proportion" with the other metal, as I now usually combine them.

Eleventh. I find great advantage in using compositions for paint in which pulverized antimony is separately mixed with colors of which the base is either tin, zinc, or lead, and the vehicle may be spirits of turpentine instead of naphtha, or the mixture of tan and naphtha herein described may be employed in whole or in part, as for the antimonial alloys.

Twelfth. The paints herein described dry very promptly, and are consequently well adapted to the paiutin g of surfaces partly of metal and partly of wood. I consequently paint both the copper or other sheathing and the planking above the sheathing, taking care to spread thin coats of tar and pitch first, and then but a thin coat at a time of the metallic paint, thus allowing the first coat to remain without becoming mixed up with the alloy paint, and consequently securing the surface a gainst the adhesion of shells and weeds.

Thirteenth. I find the metallic paints herein described to be advantageously used with a preparatory coating formed by mixing fifteen pounds of tar, fifteen pounds of pitch or of wood-charcoal, with two to three pounds of tallow or sperm-oil and from seven to ten pounds of chimney-soot well dried and sifted. The tar is first heated in a kettle, the pitch or charcoal is added, and the tallow and soot stirred in by degrees to prevent sudden swelling up and loss.

Fourteenth. This material for the preparatory coating may be dissolved or softened in naphtha to render it easy of application.

Fifteenth. In order that the oxide of copper may be of a character best suited to the purpose of mi-xin g with the antimonial paint, I prepare it out of old sheathing-copper, folded together, placed in a receptacle or case made of copper, but having several passages around its sides for the free admission air. The case is set over a fire and the whole heated up to a temperature at which sulphurwill combine with the copper, (which need not be so high as a red heat,) and then sprinkle among the folded plates at the open top of the case a quantity of powdered sulphur to the amount of about eleven and ahalf pounds of sulphur for every twenty pounds of copper. The first portion of sulphur is allowed to exhaust itself before another is added. When all the sulphur has been thrown on I cover the box with thin plates of iron or of copper, thereby maintaining the red heat then acquired by the copper sheets.

The sulphuret of copper thus formed is cooled,

2. Combining antimonial alloys with oxideof copper to constitute, with the painting-vehicles herein specified, the exterior coatings for ships bottoms for the purpose of more effectually defending them against the adhesion of shells and weeds, substantially as herein set orth.

CHAR LES \VETTERSTEDT.

Witnesses J ULs OLIVER, P. BLOHORN. 

